The conventional linear moving mechanism generally comprises a sliding base and a rail assembly which longitudinally extends. The sliding member and the rail assembly each provide at least one rail so as to form one loaded path. The sliding base provides one unloaded path and two direction change paths relative to the loaded path. The two direction change paths connect between the exits and entries of the loaded path and the unloaded path so as to form an endless circulation path. The rollers move endlessly between the loaded path, the direction change paths, and the unloaded path. By the movement of the rollers, the sliding base endlessly moves along the endless circulation path.
In order to prevent impact between the rollers, the sliding base provides retainers which are located between the rollers and connected between two side strips. The rollers are then separated by the retainers to ensure the smooth movement of the roller retaining chain.
Taiwan Patent Application No. 101100196, which titled “Roller Maintaining Chain and Method for Making Roller Maintaining Chain and Linear Movement Device” and is a prior invention of the inventor of the present invention, discloses a covering face located on each of the retainers that are adjacent the holes of the chain, a portion of the covering face is a contacting surface that is perpendicular to the longitudinal direction of the rail and another portion of the covering face is an inclined surface. The chain can be made by way of tilt injection molding which means the two side molds are separated from each other along an inclined line. The contacting surface pushes and guides the rollers to move forward and the inclined surface retains the rollers. The rollers do not drop from the holes even if the chain is removed from the endless circulation path. However, in practical use, the inventor finds that when the contacting surface pushes the rollers to move forward, a single contact point is formed between the roller and the contacting surface, the single contact point makes the rollers sometimes tilt and generate vibration. The vibration affects the movement of the sliding base.
The present invention intends to provide a roller retaining chain for improving the shortcomings mentioned above.